PROGRAM ConnectedWeb;

VAR
  a0,r0,d,a9,a,r,x,y : real;
  i,j,k,l,n,p : integer;
{$i diablo.lib }

BEGIN
  writeln('This program, connected web, was developed and coded by');
  writeln('Joe Jacobson, and is based on a suggestion by Chris');
  writeln('Kuebler. Parameter N gives the # of vertices. P gives the');
  writeln('# of imaginary tic markes on each vertex axis. A0 is the');
  writeln('initial rotation angle. R0 is the overall radius. The');
  writeln('overlay enhances the picture. For example, try:');
  writeln('(N,P,A0,R0)=(16,20,0,50) and request an overlay when asked.');
  writeln('This gives a fairly neat pattern.');
  writeln;
  write('Enter N,P,A0,R0.  ');
  readln(n,p,a0,r0);
  write('Enter 1 for single pattern, 2 for overlay.');
  readln(k);
  d := r0/p;
  a9 := 360/n;
  init_diablo;
  FOR l := 1 TO k DO
    BEGIN
      FOR i := 0 TO p-1 DO
        FOR j := 0 TO n DO
          BEGIN
            a := (a0+j*a9)*3.141592/180;
            r := ((p-i)*(j and 1)+(i+1)*((j+1) and 1))*(d);
            x := (250+r*cos(a));
            y := (250+r*sin(a));
            IF j=0 THEN
              plot(round(x),round(y))
            ELSE
              drawto(round(x),round(y))
          END;
      a0 := a0 + a9/2
    END;
  reset_diablo
END.